Apron clearer arrangement



y 12, 1964 R. B. NEWTON 3,132,384

APRON CLEARER ARRANGEMENT Filed Dec. 12, 1960 INVENTOR; RUSSELL a. NEW-TON United States Patent 3,132,384 APRON (JLEARER ARRANGEMENT Russell E. Newton, Spartanbnrg, &1, assignor to Bearing Miiliken Research orporation, Spartanhnrg, S.C., a corporation of Delaware Fiied Dec. 12, 196i), Ser. No. 75,339 Claims. (Cl. lie-245) This invention relates to textile fiber handling appa ratus, and more particularly to an improvement in the art of drafting textile fibers through the medium of an apron or aprons, being specifically directed to the improved postitioning :of the apron and the reduction or elimination of lint and the like in the area within the apron or aprons.

'In the drafting of textile fibers for the purpose of forming a spun yarn or a roving or the like of staple fibers, it is desirable to maintain a control over the fibers in the zone between the adjacent drafting rolls, and particularly the area between the middle and front rolls inasmuch as these rolls provide a comparatively high draft in most modern frames. In order to effect this control it is conventional practice to employ an apron or aprons extending from the middle pair of rolls to a position adjacent the front pair of rolls. Examples of this type of system are the Casablancas, Roth, and Duo-Roth drafting systems. In each of these systems one or more aprons is employed to maintain fiber control between the middle and front pairs of rolls.

Several problems arise from the practical use of these systems, one important problem being the accumulation of lint or fly within the apron and about the roll and/or nose bar on which the apron rides. This accumulation of lint causes variation in the drafting action due to the resulting change in spacing between the aprons, as well as the effective change in size of the apron roll and/ or nose bar.

A further difiiculty is the tendency of the apron or aprons to buckle in the fiber control zone, or in other words in the zone where the apron or aprons engage the fibers. This difiiculty is particularly present after the aprons have run for a substantial time and become stretched beyond their original size. Accumulations of lint on the apron roll and/ or nose bar cause this stretching and buckling to assume a washboard or wavy shape. As a result of this buckling and Washboarding effect of the apron or aprons in the fiber control zone between the middle and front drafting rolls the control of the fibers is naturally reduced, and varies dependent upon the direction of buckling, or in other Words whether the apron buckles or curves toward or away from the fibers. It is desirable that there be a certain amount of lateral resilience of the apron in the fiber control zone formed by the apron or aprons. This has normally been effected by employing a combination of a roll and a stationary nose bar for supporting the apron, with an intermediate zone therebetween in which the apron is unsupported and free to move laterally up and down. Theoretically, the apron should tend to bow convexly outwardly in the zone between its drafting roll and nose bar, but in actual practice, particularly after long and continued use, the apron does not always exert a bowing force in this desired manner, but instead may bow inwardly or have a more or less washboard bowing lengthwise and/or widthwise in the fiber control zone between the drafting roll and the nose bar.

While various attempts have been made to solve this latter problem of controlling the position of the apron in the fiber control zone between the drafting roll and the nose bar therewithin, to my knowledge none of these solutions has been entirely successful, and particularly such solutions have failed to overcome the first difliculty mentioned above wherein lint or fly or the like tend to Patented May 12, 1964 "ice accumulate within the apron and particularly about the drafting roll.

Accordingly, a major feature of the present invention lies in the provision of an improvement in apron drafting apparatus which tends to minimize the foregoing mentioned difficulties of lint accumulation within the apron interior and about the apron drafting roll and/or nose bar, and the variation in control action on the fibers in the zone between the drafting rolls due to buckling or other variations in the position of the apron or aprons in this zone.

A still further feature lies in the improved drafting action, particularly in the more even drafting of the fibers, as reflected in a minimizing or reduction of end breakage or ends down of the yarn formed with drafting apparatus utilizing the present invention.

A still further feature lies in the provision of an improved apron drafting arrangement which minimizes lint accumulation Within the apron interior and provides for desired position control of the apron in the fiber control area through the provision of a single apron-and-rollengaging unit which serves the combined functions of nose guide for the apron, minimizing or substantially eliminating lint accumulation within the apron, and position control of the apron, particularly in the fiber control zone of the apron.

Still other features and attendant advantages will become apparent to those skilled in the art from a reading of the following detailed description of various embodiments constructed according to the invention, taken in conjunction with the accompanying drawings, wherein:

FIGURE 1 is a side elevation of a drafting arrangement incorporating the invention.

FIGURE 2 is a view in perspective of one of the apron positioning and clearing members of FIGURE 1.

FIGURE 3 is a view in perspective of the apron section of the arrangement of FIGURE 1.

FIGURE 4 is a side elevation view illustrating an alternative embodiment according to the invention.

FIGURES 5 and 6 are fragmentary views of two further modified drafting arrangements according to the invention.

Referring now to the embodiment of FIGURES 1-3, the invention is illustrated as applied to a Casablancas type drafting arrangement having two fiber supporting aprons. Thus, as seen in FIGURE 1, the fibers of roving, sliver, or the like 11 are passed through a suitable guide, such as a trumpet 13, to a first pair of drafting rolls 15, from which the fibers pass to a second pair of rolls 17a, 17b carrying a pair of fiber supporting aprons 19a, 1911 which serve to support and guide the fibers being drafted in the zone between the nip of the middle pair of rolls 17a, l17b and the nip of the succeeding third pair of rolls 21. From the third pair of rolls the strand of drafted fibers pass to a suitable twisting and takeup arrangement (not shown). In accordance with conventional practice, each of the succeeding pairs of rolls 15, 17, and 21 may be driven at a suitable increasing surface velocity in order to effect the desired degree of drafting between each of the adjacent pairs of rolls.

According to the invention, an apron positioning and clearing member 23 is disposed within at least one of the two aprons 19a, 1917, or in the case of a single apron system is incorporated within the single apron, and extends between and in engagement with the circumferential periphery of the associated 17a, 17b and the front smaller radius of curvature nose portion of the respective apron. In the example of FIGURES 1-3, each of the two aprons has an apron positioning and clearing member '23 disposed there-within, which not only serves to clear the interior of the respective apron of substantially all lint or other foreign material, but also eliminates the necessity for a nose bar as is commonly used in conventional practice with apron drafting systems, in that it serves to position the fiber-engaging run 19a1, 19b1 of the respective apron in the desired location adjacent the fiber flow path, thus maintaining the fibers in their orderly turn or relationship.

Each of the two apron clearing and positioning members may be formed in substantially the same shape, as illustrated in FIGURES 1-3 and particularly FIG- URE 2, with the lower of the two members 23 being inverted relative to the upper member, although different configurations may be necessary or desirable for each of the two aprons in some instances. As seen in FIGURES 1 and 2 particularly, the apron positioning and clearing member takes the form of a block having a generally tapered configuration, and formed of any suitable material, such as Micarta, Bakelite, polyethylene, Delrin, metal, or the like.

In the embodiment of FIGURE 1 each of the apron clearing and positioning members 23 is a block formed with a concave surface 23a at one end having a radius of curvature substantially corresponding to the external radius of curvature of the corresponding roll 17a or 171) of the middle roll pair. The block 23 is tapered from this large end toward the front small end to a nose 23b having a radius of curvature which is relatively small, for instance of the order of V ,4; inch radius, and which if desired may have an even smaller radius of curvature in order to permit the aprons to extend as close as possible to the nip of the front roll pair 21, 21 and thereby provide the maximum support and control of the fibers during their passage from the middle roll pair 17a, 17b to the front roll pair 21, 21. As a further aid to close disposition of the aprons to the nip of the front pair of rolls 21, 21 each apron may be formed of thinner sheet material than has heretofore been possible, due to the fact that the apron is positioned and supported in the fiber engaging zone by the apron clearing and positioning member 23.

In the arrangement of FIGURE 1 the surface of the apron positioning and clearing member 23 is substantially straight between the large concave roll-engaging end 23a thereof and the convex smaller radius nose end 2312 thereof on the side 23c engaged by the fiber-engaging run 19(11, 19111 run of the respective apron. The opposite tapered surface 23d of the apron positioning and clearing member 23 may be either straight or convex (as shown) in order to provide substantially full support and engagement of the apron by the member, to the end that the apron is not only supported but that any external foreign material is substantially prevented from entering the zone within the apron. Also, the leading edge 23:11 of the concave end 23a of the clearer block serves as a scraper on both the respective roll 17a, 17b and the interior surface of the apron to aid in keeping the zone within the apron clear of lint and the like.

The apron positioning and clearing members may be supported in the desired position through the medium of a pin or pins, which may suitably engage in an aperture or apertures formed in the members. In the illustrated embodiment the two positioning and clearing members 23 are secured in position by a U-shaped pin 25, the legs 25a of which extend through complementary apertures 27 in the side walls 31 of the supporting cradle 29, as seen in FIGURE 3, and into corresponding apertures 23 formed in the respective clearing and positioning block 23. In order to provide for movement of the two aprons toward and away from one another along the path of travel of the fibers the apertures or bores 23f formed in the respective blocks may in one or both instances be oversize compared to the portion of the pin 25 extending therein. Thus, in the arrangement of FIGURE 1 the upper apron 19a and associated apron positioning and clearing member 23 may move upwardly about the axis of he roll 17a through a restricted extent of travel corresponding to the amount of lateral free play between the pin 25 and the corresponding bore 23 While the apron positioning and clearing members are illustrated as being movable toward and away from one another in order to accommodate variations in the material passing therebetween, in some instances it may be desirable to mount these clearing and positioning members in a fixed manner, in which case the mounting and supporting pin may fit in substantially complementary relation into the bore or apertures 23 formed in the clearing and positioning member 23.

In the modification of FIGURE 4 the two clearing and positioning block members 23 may be identical to the clearing and positioning block members 23 illustrated in FIGURE 1. In this embodiment, however, each of the clearing and positioning blocks 23 is supported in the desired position through the medium of a pin formed or secured on a leaf spring 127 which is in turn secured as by a brad 129 to the outer surface of the cradle side Wall 131. The ends, which are seen only in broken lines, may suitable extend into corresponding apertures formed in the side walls and fit into the bore or other aperture 23 formed in the corresponding apron positioning and clearing block. While only one leaf spring 127 and pin 125 is illustrated in FIGURE 4 for each of the two clearing and positioning blocks 23, it will be apparent that another identical but oppositely extending leaf-spring-supported pin 125 may be secured to the opposite cradle wall for supporting each of the two clearing and positioning members 23 if desired. As in the example of FIGURES 1-3, the pin and bore connection may be either loose fit for freedom of movement of one or both of the apron positioning and clearing members or form a substantially complementary tight fit for substantially fixed positioning of the apron positioning and clearing members.

In the alternative embodiment according to FIGURE 5 the invention is illustrated as applied with only the top apron 219a having an apron positioning and clearing member 223 disposed therein. The single apron positioning and clearing member 223 is in this instance preferably fixed in position, with substantially no provision for lateral movement toward and away from the lower apron, through the medium of a complementary pin 22-5 extending through the side wall of the supporting cradle, the cradle wall being omitted from the drawing for purposes of clarity of illustration of the clearing and positioning member and aprons.

It is an important aspect of this embodiment of the invention that the tapered surface 223cof the apron positioning and clearing member adjacent the fiber engaging run of the apron 219a is convex. The radius of curvature or average radius of curvature of this convex surface may be relatively large, the important aspect lying in the convex curvature of the surface 223c in order to better conform the two adjacent runs 219611, 219b1 of the aprons to one another along the fiber engaging portion of their travel. Thus, the upper apron 21% is caused to assume a substantially outwardly bowed configuration along its fiber engaging run 219121, whereas the lower apron 21% assumes an elastically flexible substantially concave configuration along the fiber engaging run 219171. It is desirable to maintain the lower apron run 219121 with a degree of lateral freedom of movement toward and away from the fiber flow path, thus providing the normally desired light resilient gripping and supporting of the fibers in the zone along the two inter-engaging runs of the aprons.

The modification of FIGURE 6 differs from that of FIGURE 5 only in that the lower apron 319D is provided with a clearing and positioning member, whereas the upper apron 319a is supported at its nose end by a conventional nose bar 335, similar to the nose bar 235 which serves to support the nose portion of the lower apron 21912 in the arrangement of FIGURE 5. It will be noted in this arrangement that the fiber engaging run 319111 of the upper apron 31% is bowed inwardly or concave,

whereas the fiber engaging run 319211 of the lower apron 31% is bowed outwardly as a result of the upper convexly curved surface 323a of the apron positioning and clearing member 323.

While the invention has been shown and described with reference to several illustrative embodiments constructed in accordance therewith, it will be apparent to those skilled in the art that various modifications and improvements may be made without departing from the scope and spirit of the invention. Accordingly, it is to be understood that the invention is not to be limited by the particular illustrative embodiments shown and described herein, but only by the scope of the appended claims.

That which is claimed is:

1. In a drafting arrangement having a fiber control flexible apron and a rotating apron supporting roll within and in engagement with said apron, the improvement comprising a normally substantially stationary apronpositioning-and-clearing and roll-clearing member disposed within said apron and extending between and in rubbing engagement with a peripheral portion of said roll and a portion of said apron spaced from said roll, said member having an apron-reversing convex nose portion spaced from said roll and engaging and guiding said apron to form a small arcuate end portion, said apron having a fiber engaging run extending between said roll and said convex nose portion and a return run also extending therebetween.

2. The improvement according to claim 1 wherein said apron-positioning-and-clearing member has a concavely arcuate portion extending in contiguous engagement with a portion of the periphery of said roll as an aid to the prevention of accumulation of lint on said roll.

3. The improvement according to claim 2 wherein said apron-positioning-and-clearing member has a surface portion extending along and in closely adjacent relation to a major portion of the inner surface of said fiber-engaging run of said apron extending between said roll and said convex nose portion in order to aid in positioning of said fiber-engaging run of the apron.

4. The improvement according to claim 3 wherein said member has a further surface portion extending in engagement with a major portion of the inner surface of said return run extending between said roll and said convex nose portion.

5. In a drafting apron cradle assembly for two rolls and two associated aprons wherein fiber-engaging runs of said aprons are in contiguous relation with each other, the combination comprising an apron-and-roll-clearing element adapted to engage in rubbing and guiding relation with the inner surface of an apron carried thereabout, said element having a roll-engaging surface at one end thereof adapted to engage in rubbing relation across the width of the apron carrying portion of a roll and having a tapered reduced size opposite apron-engaging-andreversing nose and an apron-run-clearing-and-guiding surface disposed between said one end and said nose and a second element having an apron-run-clearing-and-guiding surface facing and operably associated with and spaced from said apron-run-clearing-and-guiding surface on said first mentioned element, said elements being removably connected together in interspacial relationship.

6. A drafting arrangement according to claim 5 wherein said second element has a roll-clearing surface disposed adjacent said apron-run-clearing-and-guiding surface and adapted to engage in rubbing relation across the Width of the apron carrying portion of the associated roll.

7. A drafting cradle arrangement according to claim 6 wherein said second element includes a tapered reduced size apron-guiding-and-reversing nose spaced from said roll-clearing surface.

8. The improvement according to claim 3 wherein said member has an aperture therein, pin means operably as sociated with said aperture to allow movement of said member toward and away from the normal fiber flow path along said apron.

9. The improvement according to claim 1 wherein said member has an aperture therein, a second member operably associated with said first mentioned member, means forming an aperture in said second member, and pin means operably associated with said apertures to fix the general position of said first mentioned member relative'to the normal fiber flow path along said apron.

10. The structure of claim 9 wherein said pin means is removably secured in said apertures, said pin means being relatively tight and snug in said apertures to firmly position said first mentioned member. a I

11. The structure of claim 9 wherein said second member is an apron-positioning-and-clearing and roll-clearingmember, a second apron supporting roll, and a second fiber control flexible apron on said second roll, said second member being positioned within said second apron and supporting one run of said second apron in contiguous relation with said fiber engaging run of said first mentioned apron. v

12. The structure of claim 11 wherein said second apron-positioning-and-clearing and roll-clearing member is movable toward and away from said first mentioned apron-positioning-and-clearing and roll-clearing member during normal fiber flow between said aprons.

13. The structure of claim 1 in combination with a second apron, a second apron supporting roll within said second apron, a second apron-positioning-and-clearing and roll-clearing member within said second apron, said second apron having a fiber-engaging run in contiguous relation with said fiber-engaging run of said first mentioned apron, said first and second aprons and associated apron-positioning-and-clearing and roll-clearing members 7 being interconnected by pin means.

14. The structure of claim 1 wherein said apron-positioning-and-clearing and roll-clearing member is a block extending along substantially the width of said apron, said block having a concave surface opposite to said apron-reversing convex nose portion engaging with said roll with a substantially larger average radius of curvature than the radius of curvature of said apron-reversing convex nose portion, and two intermediate surfaces of substantially greater average radius of curvature than said apron-reversing convex nose portion and joining with said apron reversing convex nose portion.

15. In a drafting arrangement having a pair of fiber control flexible aprons, each of which have a rotating apron-supporting roll within and in engagement therewith, each of said aprons having an outer face, the outer faces of said aprons being contiguous with one another along a respective fiber engaging run thereof extending from their respective roll to a terminal reversal zone spaced from said rolls, the improvement comprising two apron-positioning-and-clearing and roll-clearing members, each of said members being disposed within a respective one of said aprons and extending between and in rubbing engagement with a peripheral portion of said roll and a portion of said apron at a position spaced from said roll and disposed in said terminal apron reversal zone, each of said members having an apron engaging portion disposed in said terminal apron reversal zone to guide the respective apron in said reversal zone.

Germany Sept. 17, 1959 Great Britain Oct. 19, 1960 

1. IN A DRAFTING ARRANGEMENT HAVING A FIBER CONTROL FLEXIBLE APRON AND A ROTATING APRON SUPPORTING ROLL WITHIN AND IN ENGAGEMENT WITH SAID APRON, THE IMPROVEMENT COMPRISING A NORMALLY SUBSTANTIALLY STATIONARY APRONPOSITIONING-AND-CLEARING AND ROLL-CLEARING MEMBER DISPOSED WITHIN SAID APRON AND EXTENDING BETWEEN AND IN RUBBING ENGAGEMENT WITH A PERIPHERAL PORTION OF SAID ROLL AND A PORTION OF SAID APRON SPACED FROM SAID ROLL, SAID MEMBER HAVING AN APRON-REVERSING CONVEX NOSE PORTION SPACED FROM SAID ROLL AND ENGAGING AND GUIDING SAID APRON TO FORM A SMALL ARCUATE END PORTION, SAID APRON 